Angular 2：如何通过CSS Selector在@ViewChild中查找子元素？

import { Component,ViewChild } from '@angular/core';
@Component({
  SELEctor: 'my-app',template: `
    <div #container>
        <p>para 1</p>
        <p class="my-class">para 2</p>
        <button>button 1</button>
    </div>
  `
})
export class AppComponent {
  @ViewChild('container') myDiv;
  ngAfterViewInit(){
    console.log(this.myDiv.nativeElement.children);
  } 
}